The procedure for correcting unbalance on a wheel such as a motor vehicle wheel typically involves using one or more compensating or balancing weights which are to be secured to the wheel, for example on the disk portion thereof, more particularly for example at the rim part thereof, in a suitable position which is ascertained by an electronic measuring arrangement during an unbalance measuring operation.
In such a procedure, dimensions of the wheel, more especially in the rim region thereof, can be ascertained by means of a sensing device and stored in the electronic measuring arrangement, for example as disclosed in German published specification (DE-AS) No 20 01 972 or the Hofmann operating instructions for the Geodyna 88/88m wheel balancing machine, imprint 9412145-09.86. That procedure provides that the electronic measuring arrangement is supplied with suitable items of information for calculating the sizes and angular positions of the balancing weights which are to be fitted to the disk portion of the wheel in the appropriate balancing planes.
A balancing machine for motor vehicle wheels is also to be found in DE 41 22 844 A1 corresponding to U.S. patent application Ser. No. 07/910,917 (U.S. Pat. No. 5,447,064), including a sensing device having a sensing lever or rod which is both pivotable and also adjustable in respect of length. That sensing device makes it possible to ascertain the dimensions of the rim of the wheel or the disk portion thereof, in the appropriate balancing planes, for the input of those dimensions into the electronic measuring arrangement, prior to the unbalance measuring operation being performed.
A further apparatus for correcting wheel unbalance is to be found in DE 42 29 865 A1 corresponding to U.S. patent application Ser. No. 08/115,779 (U.S. Pat. No. 5,471,874). That apparatus includes an extensible and pivotable sensing lever or rod having a sensing tip for sensing dimensions of the disk portion of a motor vehicle wheel to be balanced. The sensing lever is operatively connected to a position detecting means for generating electrical position detection signals corresponding to the respective extension length and pivotal position of the sensing lever. The position detection signals can be stored in a storage means. That apparatus further includes an electronic measuring and evaluation arrangement for evaluating measuring sensor signals which are obtained in the unbalance measuring operation, in the measuring runs carried out on the wheel requiring balancing. Those signals are stored in the storage means, constituting information in respect of magnitude and angular position, in relation to the balancing planes, for the balancing weight or weights required to be fitted to the wheel for balancing thereof. After a given balancing weight has been fitted into a weight holder which is mounted on the sensing lever at the front end thereof, the sensing lever is moved to the appropriate balancing position on the wheel. The apparatus includes a comparison means for detecting the approach to the stored position, and indicating same by means of a suitable display device. Therefore, by moving the sensing lever towards the wheel and turning the wheel into a given angular position, while observing the display afforded by the display device, the operator will find the correct balancing position for fitting the balancing weight to the wheel.